The article analyzes the last two decades of East-Central European countries along the principal dimensions of party systems. It also investigates the relation ships among the various attributes of party competition. The authors regard polarization, fragmentation, closure (introduced by Peter Mair) and volatility as principal dimensions of party systems, but they argue that the qualitative characteristics of party relationships are as relevant as these much re search ed standard dimensions. They draw attention and systematically scru tinize questions such as how durable the alliances among parties are, how consequential ideological similarities are in government building, and how many and what kind of ideological camps exist in a given party system. The examination of the data proves that for most of the analyzed period party relations were more crys tallized in Hungary and the Czech Republic than in Slovenia, Estonia, Bulgaria and Latvia, while the other countries of the region were situated between these two groups. With the exception of volatility the analyzed indicators moved rather closely together, indicating that it is legitimate to talk about a syndrome of institutionalization. Since the party elites have relatively little control over volatility, the latter variable is not an integral part of the syndrome.